334 citations · 4k across the 75 of their papers we have counts for
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Inflation with
Mohammad Ali Gorji, Hayato Motohashi, Shinji Mukohyama
We investigate a novel single field inflationary scenario which allows a transition between a slow-roll k-inflation with of order unity and a ghost inflation with $ c_{…
Effective field theory of degenerate higher-order inflation
Hayato Motohashi, Wayne Hu
We extend the effective field theory of inflation to a general Lagrangian constructed from Arnowitt-Deser-Misner variables that encompasses the most general interactions with up to…
Quantum Ostrogradsky theorem
Hayato Motohashi, Teruaki Suyama
The Ostrogradsky theorem states that any classical Lagrangian that contains time derivatives higher than the first order and is nondegenerate with respect to the highest-order deri…
Ghost-free theories with arbitrary higher-order time derivatives
Hayato Motohashi, Teruaki Suyama, Masahide Yamaguchi
We construct no-ghost theories of analytic mechanics involving arbitrary higher-order derivatives in Lagrangian. It has been known that for theories involving at most second-order…
Ghost-free theory with third-order time derivatives
Hayato Motohashi, Teruaki Suyama, Masahide Yamaguchi
As the first step to extend our understanding of higher-derivative theories, within the framework of analytic mechanics of point particles, we construct a ghost-free theory involvi…
Generalized Slow Roll in the Unified Effective Field Theory of Inflation
Hayato Motohashi, Wayne Hu
We provide a compact and unified treatment of power spectrum observables for the effective field theory (EFT) of inflation with the complete set of operators that lead to second-or…